Ultrastructural changes and asthenozoospermia in murine spermatozoa lacking the ribosomal protein L29/HIP gene

RpL38 modulates germ cell differentiation by controlling Bam expression in Drosophila testis

Switching from mitotic spermatogonia to meiotic spermatocytes is critical to producing haploid sperms during male germ cell differentiation. However, the underlying mechanisms of this switch remain largely unexplored. In Drosophila melanogaster, the gene RpL38 encodes the ribosomal protein L38, one component of the 60S subunit of ribosomes. We found that its depletion in spermatogonia severely diminished the production of mature sperms and thus led to the infertility of male flies. By examining the germ cell differentiation in testes, we found that RpL38-knockdown blocked the transition from spermatogonia to spermatocytes and accumulated spermatogonia in the testis. To understand the intrinsic reason for this blockage, we conducted proteomic analysis for these spermatogonia populations. Differing from the control spermatogonia, the accumulated spermatogonia in RpL38-knockdown testes already expressed many spermatocyte markers but lacked many meiosis-related proteins, suggesting that spermatogonia need to prepare some important proteins for meiosis to complete their switch into spermatocytes. Mechanistically, we found that the expression of bag of marbles (bam), a crucial determinant in the transition from spermatogonia to spermatocytes, was inhibited at both the mRNA and protein levels upon RpL38 depletion. We also confirmed that the bam loss phenocopied RpL38 RNAi in the testis phenotype and transcriptomic profiling. Strikingly, overexpressing bam was able to fully rescue the testis abnormality and infertility of RpL38-knockdown flies, indicating that bam is the key effector downstream of RpL38 to regulate spermatogonia differentiation. Overall, our data suggested that germ cells start to prepare meiosis-related proteins as early as the spermatogonial stage, and RpL38 in spermatogonia is required to regulate their transition toward spermatocytes in a bam-dependent manner, providing new knowledge for our understanding of the transition process from spermatogonia to spermatocytes in Drosophila spermatogenesis.

Food from Equids-Commercial Fermented Mare's Milk (Koumiss) Products: Protective Effects against Alcohol Intoxication

Fermented mare's milk (koumiss), a traditional Central Asian dairy product derived from fermented mare's milk, is renowned for its unique sour taste and texture. It has long been consumed by nomadic tribes for its nutritional and medicinal benefits. This study aimed to comprehensively analyze the protective effects of koumiss against alcohol-induced harm across behavioral, hematological, gastrointestinal, hepatic, and reproductive dimensions using a mouse model. Optimal intoxicating doses of alcohol and koumiss doses were determined, and their effects were explored through sleep tests and blood indicator measurements. Pretreatment with koumiss delayed inebriation, accelerated sobering, and reduced mortality in mice, mitigating alcohol's impact on blood ethanol levels and various physiological parameters. Histopathological and molecular analyses further confirmed koumiss's protective role against alcohol-induced damage in the liver, stomach, small intestine, and reproductive system. Transcriptomic studies on reproductive damage indicated that koumiss exerts its benefits by influencing mitochondrial and ribosomal functions and also shows promise in mitigating alcohol's effects on the reproductive system. In summary, koumiss emerges as a potential natural agent for protection against alcohol-induced harm, opening avenues for future research in this field.

Effect of Dimethylacetamide Concentration on Motility, Quality, Antioxidant Biomarkers, Anti-Freeze Gene Expression, and Fertilizing Ability of Frozen/Thawed Rooster Sperm

Sperm cryopreservation is of great importance for the poultry industry but still needs to be optimized. The high susceptibility of poultry sperm to cryodamage leads to low fertility rates after cryopreservation. Therefore, the present study aimed at evaluating the effect of including a cryoprotectant, dimethylacetamide (DMA), in the chicken semen freezing extenders at a final concentration of 3%, 6%, or 9% on the post-thawed sperm motility, quality, antioxidant biomarkers, anti-freeze gene expression, and fertilizing ability. Results showed that the total motile sperm, progressivity, and viability were quadratically increased (p < 0.05) in the 6% DMA group. The antioxidant enzyme activity and lipid peroxidation were negatively (p < 0.05) affected by the increase in DMA concentration. Furthermore, some anti-freeze-associated genes such as heat shock protein 70 (HSP70) and ras homolog family member A (RHOA) were linearly and quadratically down-regulated (p < 0.05) with the high concentration of DMA. Finally, the fertility and hatchability rates did not indicate statistical differences between DMA groups. It can be concluded that using the low concentration of 3−6% DMA in the freezing semen extender is preferable to obtain acceptable results in the post-thawed sperm quality and fertility.

Organic mineral supplementation on differential protein profile of Osmanabadi bucks (Capra hircus)

The present study aimed to determine the differential protein profile of seminal plasma proteins of bucks supplemented with trace minerals. Forty bucks of uniform size and body weight were assigned as ten groups (n = 4). The control group (T1) was fed with the control diet (concentration mixture and roughages) whereas the remaining groups were supplemented the control diet with Zn20 mg (T2), Zn40 mg (T3), Zn60 mg (T4), Cu12.5 mg (T5), Cu25 mg (T6), Cu37.5 mg (T7), Zn20 mg + Cu12.5 mg (T8), Zn40 mg + Cu25 mg (T9), and Zn60 mg + Cu37.5 mg (T10) for eight months. Seminal plasma proteins from each group were subjected to two-dimensional electrophoresis and fifteen differential proteins were selected based on differential expression, subjected to identification using Nano-LC-MS/MS (LTQ-Qrbitrap-MS). The identified proteins were Triacylglycerol lipase, EGF like repeats and discoidin domains 3, Lipocalin, Iodothyronine deiodinase, Transcription factor AP2-delta, 60S ribosomal protein L13, IST1 factor associated with ESCRT-III, Lysozyme, Uncharacterized protein (BRI3-binding protein), Uncharacterized protein, Histone deacetylase 11, General transcription factor IIF subunit 2, Nudix hydrolase 6, Protein kinase cAMP-activated catalytic subunit beta and Elongin C. The organic Cu supplemented group is the better than the organic Zn and organic Zn + Cu supplemented groups.

Ribosome heterogeneity and specialization in development

Regulation of protein synthesis is a vital step in controlling gene expression, especially during development. Over the last 10 years, it has become clear that rather than being homogeneous machines responsible for mRNA translation, ribosomes are highly heterogeneous and can play an active part in translational regulation. These "specialized ribosomes" comprise of specific protein and/or rRNA components, which are required for the translation of particular mRNAs. However, while there is extensive evidence for ribosome heterogeneity, support for specialized functions is limited. Recent work in a variety of developmental model organisms has shed some light on the biological relevance of ribosome heterogeneity. Tissue-specific expression of ribosomal components along with phenotypic analysis of ribosomal gene mutations indicate that ribosome heterogeneity and potentially specialization are common in key development processes like embryogenesis, spermatogenesis, oogenesis, body patterning, and neurogenesis. Several examples of ribosome specialization have now been proposed but strong links between ribosome heterogeneity, translation of specific mRNAs by defined mechanisms, and role of these translation events remain elusive. Furthermore, several studies have indicated that heterogeneous ribosome populations are a product of tissue-specific expression rather than specialized function and that ribosomal protein phenotypes are the result of extra-ribosomal function or overall reduced ribosome levels. Many important questions still need to be addressed in order to determine the functional importance of ribosome heterogeneity to development and disease, which is likely to vary across systems. It will be essential to dissect these issues to fully understand diseases caused by disruptions to ribosomal composition, such as ribosomopathies. This article is categorized under: Translation > Translation Regulation Translation > Ribosome Structure/Function RNA in Disease and Development > RNA in Development.

The tissue specific regulation of miR22 expression in the lung and brain by ribosomal protein L29

Endogenous miR22 is associated with a diverse range of biological processes through post-translational modification of gene expression and its deregulation results in various diseases including cancer. Its expression is usually tissue or cell-specific, however, the reasons behind this tissue or cell specificity are not clearly outlined till-date. Therefore, our keen interest was to investigate the mechanisms of tissue or cell-specific expression of miR22. In the current study, miR22 expression showed a tissues-specific difference in the poly(I:C) induced inflammatory mouse lung and brain tissues. The cell-specific different expression of miR22 was also observed in inflammatory glial cells and endothelial cells. The pattern of RPL29 expression was also similar to miR22 in these tissues and cells under the same treatment. Interestingly, the knockdown of RPL29 exerted an inhibitory effect on miR22 and its known transcription factors including Fos-B and c-Fos. Fos-B and c-Fos were also differentially expressed in the two cell lines transfected with poly(I:C). The knockdown of c-Fos also exerted its negative effects on miR22 expression in both cells. These findings suggest that RPL29 might have regulatory roles on tissue or cell-specific expression of miR22 through the transcription activities of c-Fos and also possibly through Fos-B.

Knockdown of the Ribosomal Protein eL29 in Mammalian Cells Leads to Significant Changes in Gene Expression at the Transcription Level

An imbalance in the synthesis of ribosomal proteins can lead to the disruption of various cellular processes. For mammalian cells, it has been shown that the level of the eukaryote-specific ribosomal protein eL29, also known as the one interacting with heparin/heparan sulfate, substantially affects their growth. Moreover, in animals lacking this protein, a number of anatomical abnormalities have been observed. Here, we applied next-generation RNA sequencing to HEK293 cells transfected with siRNAs specific for the mRNA of eL29 to determine what changes occur in the transcriptome profile with a decrease in the level of the target protein. We showed that an approximately 2.5-fold decrease in the content of eL29 leads to statistically significant changes in the expression of more than a thousand genes at the transcription level, without a noticeable effect on cell viability, rRNA level, and global translation. The set of eL29-dependent genes included both up-regulated and down-regulated ones, among which there are those previously identified as targets for proteins implicated in oncogenesis. Thus, our findings demonstrate that an insufficiency of eL29 in mammalian cells causes a significant reorganization of gene expression, thereby highlighting the relationship between the cellular balance of eL29 and the activities of certain genes.

Comparative transcriptome analysis digs out genes related to antifreeze between fresh and frozen-thawed rooster sperm

The objective of this study was to investigate differences in mRNA expression between fresh and frozen–thawed sperm in roosters. In trial 1, gene expression profiles were measured using microarray with Affymetrix GeneChip Chicken Genome Arrays. The results showed that 2,115 genes were differentially expressed between the 2 groups. Among these genes, 2,086 were significantly downregulated and 29 were significantly upregulated in the frozen–thawed sperm group. Gene Ontology (GO) analysis showed that more than 1,000 differentially expressed genes (DEG) of all significantly regulated genes were involved in GO terms including biological processes, molecular function, and cellular component. Kyoto Encyclopedia of Genes and Genomes analysis showed that DEG were significantly (P < 0.05) enriched on ribosome, oxidative phosphorylation, proteasome, cell cycle, oocyte meiosis, and spliceosome pathways. In trial 2, ejaculated semen was collected from 18 roosters and divided into 5 recombinant HSP90 protein–supplemented groups (0.01, 0.1, 0.5, 1, or 2 μg/mL) and one control group with no recombinant HSP90 protein supplementation to evaluate the effect of recombinant HSP90 protein in the extender on post-thaw quality of rooster semen. The results showed that post-thaw sperm viability and motility was significantly improved (P < 0.05) in the extender containing 0.5 and 1 μg/mL of recombinant HSP90 protein compared with the control. Our preliminary results will provide a valuable basis for understanding the potential molecular mechanisms of cryodamage in frozen–thawed sperm and theoretical guidance to improve the fertility of frozen–thawed chicken sperm.